Baidu started a Twitter-like site called Baidu Talk which also had more full-fledged social networking features and required real identities a la Facebook. After an initial growth spurt the service seems to have stalled.

The company also acquied a social network called Mayi.com which apparently isn't going anywhere, although that site's founder is reportedly in charge of Baidu's social initiatives.

Anyway, it's highly unlikely that Baidu Weibo will catch up to the highly popular Sina Weibo.

But in any case, it's interesting to think that there might be something in the DNA of a search company that's just utterly incompatible with social DNA.